1. The Field of the Invention
The present invention relates generally to tooth extraction devices. More particularly, it concerns a tooth root tip extractor for extracting severed tooth roots from the mouth of a patient.
2. The Background Art
A problem occurs in the field of dentistry when the crown of a tooth breaks apart from the root of the tooth, leaving the root behind and embedded in the bone. This can occur in several different settings, such as during a formal tooth extraction procedure by a dentist, or when the crown of a tooth is inadvertently fractured loose during heaving physical activity, or in any other manner.
FIG. 1 illustrates schematically a jaw bone 14, gum tissue 16, tooth crown 18 and a nerve 20 of the tooth 10. The root 12 of the tooth 10 often fuses directly to the jaw bone 14, which causes the root 12 to break along severance path 22 during extraction or fracturing of the tooth 10. FIG. 2 shows the condition of a tooth root 12 that has been left behind after removal of the majority of the tooth 10 of FIG. 1. A substantial amount of effort is required to extract the severed tip of the root 12, especially when it has fused with the jaw bone 14.
Conventional methods of extracting the broken tip of the root 12 include simply drilling out part of the jaw bone 14, then digging out the root tip with a sharp member known as a tooth root "pick" or "elevator." Such prior art tooth root extraction procedures are astonishingly unsophisticated, and perhaps even barbaric in nature, and yet they are still being used today. As shown in FIG. 2, pick 24 is applied to simply pry the severed tooth root 12 loose from the jaw bone 14, which often causes painful damage to surrounding gum tissue 16 and to the jaw bone 14.
In some cases, dentists will loosen the tooth root 12 with the pick 24, then use a root pick elevator to elevate the tooth root 12 and a forceps 26 (FIG. 3) to grasp the tooth root 12 and extract it. This requires the dentist to drill out a sufficient amount of jaw bone 14 with a conventional dental drill to make room for the bulky forceps 26 and root pick elevator to access the tooth root 12.
Such procedures cause a lot of the jaw bone 14 and associated nerves and blood vessels to be needlessly removed and damaged sometimes causing a "dry socket" condition which prevents blood from clotting in the extraction site. There is of course increased trauma to the patient, and a slower healing process, as a result. These prior art procedures are not only barbaric but also require a lot of time, and therefore more money in terms of the dentist's time to perform the procedure.
Attempts have been made to overcome the disadvantages of using the tooth root pick 24 and forceps 26. For example, U.S. Pat. Nos. 2,210,349 (issued on Aug. 6, 1940 to Van Beeck) and 4,443,196 (issued Apr. 17, 1984 to Rico) illustrate tooth root extractors having a threaded screw-like member that can be rotatably screwed into the tooth root and lodged therein, after which the user extracts the screw-like member and thereby lifts the root from the jaw bone.
Such devices have not caught on in the field of dentistry, and are characterized by disadvantages. The screw member introduces a splitting action within the tooth root as it is wedged into the tooth root, and thereby achieves an unstable grip within the tooth in some cases. Sometimes the screwing and splitting action will actually cause the root to split apart prematurely, thereby further complicating the extraction procedure.